You'll need a £32,000 budget for the entry-level SE version and the range then steps up through Luxury and F Sport models, topping out with the Premier trim for which a £45,000 budget is needed. Essentially, you're looking at a £7,500 saving if you go for this 178bhp GS 300h rather than the 286bhp GS 450h model in the same spec. The GS 300h model's same 178bhp petrol/electric hybrid engine is used in the smaller BMW 3 Series-sized Lexus IS 300h but a comparably-specced version of one of those would save you just £2,000 over this GS.
In terms of trim levels, the SE is the one to go for is you're really serious about shaving your tax bill, as its 17-inch wheels just do enough to squeak it into a lower tax bracket than its siblings. It's pretty well equipped even though it is the base model, customers getting 10 airbags, electric steering wheel adjustment, a 12-speaker sounds system with DAB radio and DVD player, cruise control, push button start, parking sensors HID (xenon) headlamps, and electrically adjustable, heated front seats. Leading options will be Lexus Premium Navigation, with a 12.3-inch display, and leather upholstery (including heating/ventilation front seat functions).
That lot wouldn't look out of place on a German rival range-topper but if you want more, Lexus will certainly oblige. Extra items in the Luxury trim include leather upholstery, navigation, 18-inch alloys and a Blind Spot Monitor pack with Rear Cross Traffic Alert, while the F Sport adds features such as exterior and interior styling elements, perforated leather sports seats, 10-spoke 19-inch wheels and Adaptive Variable Sports Suspension. At the top of the range, the GS 300h Premier features a Mark Levinson 17-speaker stereo system, 18-way electric front seat adjustment with memory, a new colour head-up display, AVS and LED fog lamps.